In the art of portable electrostatic air purifiers, there have been various designs either constructed or proposed, such as, for example, the air purifiers disclosed in U.S. Pat. Nos. 2,979,158, 3,191,362 and 3,745,750. In the design of such a unit, it is not only desirable for the unit to be compact in size, but also to be effective in operation so that the unit will effectively separate or remove sub-micron particles as well as larger particles within the air in the room or area where the purifier is to be used. It is also desirable for the air purifier unit to be constructed so that the particle separating and filter components may be easily and conveniently removed for cleaning or replacement. It is further desirable for a portable electrostatic air purifier to be constructed for operation from either a 120 volt AC power supply or from a twelve volt DC power supply so that the purifier has a wide range of uses and may be used not only in the home or office but also in motor vehicles such as a recreational vehicle, bus or trailer or cabs of mobile equipment.